This disclosure relates generally to a metering device with control functionality and method thereof, and more particularly to a metering device with control functionality for providing for integration of first and second operations on an input signal within the metering device, wherein the first and second operations have first and second biasing requirements.
An electrical power utility system performs one or more functions, such as generating, transmitting, distributing, measuring, and monitoring energy. Such an electrical power utility system may utilize, for example, a grid of power lines, transformers, circuit breakers, meters, display devices, processors, etc. One type of power utility system is a power substation. Power lines deliver energy to power substations for the power substation to operate on the energy, such as for performing operations including step-up operations, step-down operations, distribution, telemetry, panel annunciation, revenue metering, detection of abnormal energy conditions and/or protection from dangerous energy conditions.
A set of external voltage and/or current transformers provide energy to a power substation equipment, where the equipment may perform more than one operation on the input energy. However, biasing requirements (e.g., component input requirements) for the equipment performing the respective operations are generally substantially different, such due to accuracy requirements and operating ranges needed for the respective operations. For example, panel metering equipment (e.g., for measuring energy usage in real-time and telemetry to an outside destination) and revenue metering equipment (e.g., for accurately measuring energy usage) have first biasing requirements in order for the panel or revenue metering equipment to operate with a high degree of accuracy on a relatively small range of low energy, such as currents ranging between 0-10 amps. Secondary protective circuit relaying equipment (e.g., for protecting equipment in the power substation from dangerous conditions, such as over voltage, under voltage, energy faults, short circuits, reverse power, etc.) have second biasing requirements in order for the protective relaying equipment to operate on a relatively large range of energy, such as currents ranging between 0-100 amps, where a high degree of accuracy is not required.
Due to the difference in biasing requirements, first digital processing equipment having a first internal transformer is used for the metering equipment, generating corresponding output signals and handling the output signals, such as for generating communication transmissions, generating a display to be displayed on a display device, generating control signals, and generating analog retransmit signals. Second digital processing equipment having a second internal transformer is used for detecting dangerous conditions, generating corresponding output signals and handling the output signals, such as for the purpose of communication transmission, display, control of protective devices, such as circuit breakers, and conversion to analog for retransmission of analog signals. The need for first and second digital and/or processing equipment to handle outputs corresponding to metering and condition detection adds to overall cost, including added cost for the additional digital and/or processing equipment, control panel size, wiring time, and complexity of the drawings and schematics. Furthermore, there is a lack of coordination between the metering and protection operations and/or processing or operating on their respective outputs. To overcome the drawbacks in the prior art, it is an aspect of the present disclosure to provide a system and method for sharing equipment to be used in conjunction with performing operations having different input, operating range and/or accuracy requirements.
Furthermore, it is an aspect of the present disclosure to provide a system and method for providing coordination between the metering and protective operations and/or processing or operating on the respective outputs.